Henry Allan Gleason was an American
botanist, plant geographer, and plant ecologist who lived from January 2, 1882
until April 12, 1975. Gleason was born in Dalton City, Il.. He began his studies
at the age of 13 and published his first contribution in The American Naturalist
while still in high school. He received his B.S. and M. A. from the University
of Illinois. After a year of fellowship with the University of Ohio and a summer
as the zoologist of invertebrates on a survey of Isle Royale, Gleason began
his studies in taxonomy under Nathaniel Lord Britton at Columbia University,
graduating with a Ph.D. in 1906.

Gleason taught at the University
of Illinois and the University of Michigan, studied tropical vegetation for
one year and delivered a lecture to the Torrey Botanical Club. After the talk,
Nathaniel Lord Britton offered Gleason a permanent position at the New York
Botanical Garden.

In his 30 years with the New York
Botanical Garden, Gleason served in a variety of capacities including curator,
head curator, and assistant director. He was acting director for 19 months between
1936 and 1938. Gleason served at various times as editor of the Garden Journal,
Addisonia, and the Bulletin. He edited revised and expanded editions of the
North American Flora and Plants of the Vicinity of New York.

One of the first ecologist, he considered
his idea that “The combination of morphological and geographical evidence
can be of greatest service in developing the phylogeny and history of a group
of plants.”was his primary theoretical contribution. He is identified
with the individualistic concept of plant association, which has had strong
influence on both ecological and geographical studies of vegetation.

Gleason’s diaries contain
pages that pertain to his field trips to what is now the Henry Allan Gleason
Nature Preserve located in the southwestern portion of the forest. The pages
describe trips made in 1904, 1910, 1962, and 1966. Gleason referred to the area
as “Devil’s Neck,” or Devil’s Tower.” In 1910,
a major article entitled, The Vegetation of the Inland Sand Deposits of Illinois
was published in the Illinois State Laboratory of Natural History Bulletin.
In that article and in his diaries he describes the plants that are unique to
the area.

Gleason was still alive when the
Illinois Nature Preserves Commission dedicated the Henry Allan Gleason Memorial
Nature Preserve. The dedication letter is dated January 25, 1971. The area known
locally as Devil’s Neck was the site where much of Gleason’s early
work and research occurred here in Illinois. This research lead Gleason to form
his individualistic concept of the plant association theory. The article was
published in the Torry Botanical Club Bulletin, 53:7-26.